Nadia was assigned problems 35 through 72 for homework last week. If Nadia did all of the problems she was assigned, how many problems did she do?
Answer: Instead of counting problems 35 through 72, we can subtract 34 from each number so we instead consider problems 1 through 38. We see that Nadia did 38 problems. Notice that she did 38 and not 37 problems.